Indexable system for select wheel alignment correction

ABSTRACT

A system for wheel alignment is provided including adjustments to camber, toe, and thrust. A sleeve is fitted over the spindle of an axle. Rotation of the sleeve relative to the spindle provides for adjustments to wheel alignment while a locking feature such as e.g., a pin, is used to maintain the selected position of the sleeve relative to the spindle. The available positions of the sleeve Crelative to the spindle are predetermined in order to provide for discrete, known adjustments to the alignment of the wheel. Numerous positions can be provided based on the range and magnitude of adjustability selected.

FIELD OF THE INVENTION

The subject matter of the present disclosure relates generally to asystem for correcting the alignment of a wheel mounted onto a hub andaxle assembly.

BACKGROUND OF THE INVENTION

The alignment of a vehicle's wheel plane WP relative to the pathtraveled by the vehicle affects not only the handling of the vehicle butalso affects the wear on the tires. As used here, alignment refers tocamber, toe, and thrust. Referring to FIG. 1, camber is the anglebetween the wheel plane WP and a vertical axis VA of the vehicle 60.Positive camber (+C) refers to an angle where the top of the wheel 50 isfarther away from the center of vehicle 60 than the bottom of the wheel50. Negative camber (−C) refers to an angle where the bottom of thewheel 50 is farther away from center of the vehicle 60 than the top.Generally speaking, camber changes of even a fourth of one degree canimpact tire wear. Abnormal tire wear has been observed in certainapplications with even smaller changes in camber angle. Free rolling(non-driven) tires in low wear rate applications are especiallysensitive to camber and thus particularly prone to developing abnormalwear if the camber angle is unfavorable.

Referring to FIG. 2, toe is the angle the wheel plane WP makes with acenterline along the longitudinal axis LA of the vehicle 60. Positivetoe (+T), also referred to as toe in, is a condition where the front ofthe wheel 50 or the wheel plane WP is pointing in or towards the centerline of the vehicle 60. Negative toe (−T), also referred to as toe out,is a condition where the front of the wheel 50 or wheel plane WP pointsout or away from the center line of the vehicle 60. Thrust is theresulting direction of travel (FDT) of an axle as opposed to thedirection that might be expected from the orientation of wheel planes WPof the wheels on the axle. Generally speaking, toe changes of evenone-tenth of a degree can have an impact on tire wear.

The typical trailer axle is made by welding a pair of spindle forgingsonto a piece of axle tubing then machining the precision surfaces ofboth spindles simultaneously in a lathe process. The resulting axle isnear perfectly straight—i.e., each spindle axis possesses zero camberand zero toe. When a typical axle is installed under a vehicle (usedherein to refer to both motorized vehicles as well as trailers) andplaced into normal operation under typical loading conditions, thecamber does not remain at zero. The axle under load, although quiterigid, flexes. The flexing of the axle occurs because the suspension isattached to the axle at load transfer points which are significantlyinboard of the ends of the axle, but the tires support the weight of thevehicle by means of attachment points which are relatively near theoutboard ends of the axle. As a result of this geometry, the weight ofthe vehicle imposes a bending moment on the axle which in turn causesupward deflection of the ends of the axle resulting in the tirespresenting a slight negative camber. As the load increases, the morenegative the camber becomes. At the typical maximum legal tandem axleload in the United States, it would not be unusual for the wheel camberangle to reach approximately 0.5 degrees. The contribution of tirealignment to tire wear can be particularly problematic with vehiclesused for transporting heavy loads.

Once the weight is removed, the axle may recover and again affect thealignment of the wheels. Because of factors such as the additional costsand amount of material that would be required, increasing the stiffnessof the axle to resolve camber issues may not be practical.

Even with the same amount of camber on each axle spindle, axle camberaffects the tires differently depending on their individual wheel endposition on the vehicle because most road surfaces (RS) are not flattransversely (orthogonal to the normal travel direction) across theroad. The road surface is either crowned or sloped (by about 1.5% onaverage) so that water will evacuate from the road surface. Trucks, inNorth America and other countries using the right side of the road forforward traffic, generally operate in the right most lane, which isusually sloped very slightly to the right. This means that as vehicle istraveling on the road way, there is a gravitational force pulling thevehicle to the right. This force is resisted through the tire contactpatch, and the tire transmits this force to the axle by transmitting therequired force opposite of the direction of pull through its interfacewith its wheel. The result is that as the tire rolls down the highway,the contact patch shifts leftward with respect to the wheel plane WP. Atfull load and at normal pressure on a typical New Generation Wide BaseSingle tire (NGWBS tire), this shift has an effect on tire shoulder wearthat is roughly the equivalent of a 0.2 degree shift in wheel camber.This means that, although the left and the right wheel may each measureapproximately −0.5 degree of camber, when the shift effect isconsidered, the effective camber angle on the left side tires isapproximately −0.7 degree, and the effective camber angle on the rightside tires is approximately −0.3 degree. As a consequence of thisphenomenon, tires on the driver side left of the vehicle usuallyexperience worse inboard shoulder wear than tires on the driver sideright of the vehicle.

When a typical tandem axle vehicle (tractor or trailer) turns, thedynamics of the vehicle favor lateral grip by the forward axle tires. Asa result, the pivot point of the vehicle shifts toward the forward axletires, and the rear axle tires will tend to have greater slip laterallyas the vehicle negotiates a turn. For this reason, the rear tires on atandem axle pair receive more scrub and have a faster wear rate than thetires on the forward axle. Scrub tends to arrest the development ofirregular wear and thus the rear tires usually are less affected by thecamber issue than are the tires on the forward axle.

As a consequence, irregular tire wear is usually worst on the inboardsurface of the LF tire. Next worst is the LR tire. The RF tire comesnext but is sometimes similar in severity to the LR. The most even wearusually is found on the RR tire depending upon the particularapplication, load, and routes normally traveled. It should be obviousthat in countries such as Australia, where drivers drive on the leftside of the road instead of the right side, such observations would bereversed.

Therefore, a need exists for improved methods and apparatus foradjusting or correcting axle alignment and, more particularly, forallowing adjustment to camber, toe, and thrust. A system that allows forselect adjustments—i.e. adjustments by discrete, predetermined amountswould be useful. Such a system that allows for a wide range in variationof adjustment and for the indexing of such adjustments would also beuseful. Additional usefulness would be provided by a system that allowsfor adjustment of the alignment of an axle using hardware that can beused for the left or right sides of the vehicle.

SUMMARY OF THE INVENTION

The present invention provides a system for wheel alignment. A sleeve isfitted over the spindle of an axle. Rotation of the sleeve relative tothe spindle provides for adjustments to wheel alignment while a lockingfeature such as e.g., a pin, is used to maintain the selected positionof the sleeve relative to the spindle. The available positions of thesleeve relative to the spindle are predetermined in order to provide fordiscrete, known adjustments to the alignment of the wheel. Numerouspositions can be provided based on the range and magnitude ofadjustability selected. Additional objects and advantages of theinvention will be set forth in part in the following description, or maybe apparent from the description, or may be learned through practice ofthe invention.

In one exemplary aspect, the present invention provides a method forindexing a wheel alignment system for a vehicle, the wheel alignmentsystem including an axle defining axial, radial, and circumferentialdirections. The axle includes a flange and a spindle onto which a sleeveis rotatably received. The axle has an outer surface of revolution aboutan axis AR_(O). The method includes the steps of choosing a total numberFP_(TOT) of a first plurality of axially-oriented apertures forpositioning on the sleeve; positioning the first plurality of apertureson the sleeve at locations uniformly apart from each other along thecircumferential direction with each at a predetermined radial distancefrom axis AR_(O); selecting a total number SP_(TOT) of a secondplurality of axially-oriented apertures for positioning on the flange;wherein SP_(TOT) and FP_(TOT) do not share any common factors other thaninteger 1; and positioning the second plurality of apertures on theflange at locations uniformly apart from each other along thecircumferential direction and at the predetermined radial distance fromaxis AR_(O). The first and second plurality of apertures provide aplurality of matching pairs of apertures that can be aligned along theaxial direction by rotation of the sleeve to provide changes in wheelalignment.

In another exemplary aspect, the present invention provides an assemblyallowing selective adjustment of wheel alignment on a vehicle. Theassembly includes an axle defining axial, radial, and circumferentialdirections. The axle includes a flange and a spindle having an outboardend and an inboard end.

A first plurality of apertures are positioned at an inboard end of thesleeve and extend along the axial direction. The first plurality ofapertures are spaced apart along the circumferential direction and atvarying radial distances from the first axis. The total number of thefirst plurality of apertures is FP_(TOT).

A second plurality of apertures are positioned on the flange near aninboard end of the spindle and extend along an axial direction. Thesecond plurality of apertures are spaced apart along the circumferentialdirection and at positioned at varying radial distances from the firstaxis. The total number of the first plurality of apertures is SP_(TOT).SP_(TOT) and FP_(TOT) do not share any common factors other thaninteger 1. The first and second plurality of apertures provide aplurality of matching pairs of apertures that can be aligned along theaxial direction by rotation of the sleeve to provide changes in wheelalignment.

A removable lock extends between the apertures of one of the matchingpairs of apertures so as to prevent the rotation of the sleeve relativeto the spindle.

These and other features, aspects and advantages of the presentinvention will become better understood with reference to the followingdescription and appended claims. The accompanying drawings, which areincorporated in and constitute a part of this specification, illustrateembodiments of the invention and, together with the description, serveto explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including thebest mode thereof, directed to one of ordinary skill in the art, is setforth in the specification, which makes reference to the appendedfigures, in which:

FIG. 1 illustrates a front view of an exemplary vehicle having wheels asmay benefit from use of the present invention.

FIG. 2 illustrates a top view of the exemplary vehicle of FIG. 1.

FIG. 3 illustrates a view (top, bottom, or side) of an exemplaryassembly of the present invention as may be used for correction of toe,camber, and/or thrust.

FIG. 4 illustrates a cross-sectional view along line 4-4 of theexemplary assembly of FIG. 3.

FIG. 5 provides an exploded perspective view of the exemplary assemblyof FIG. 3.

FIG. 6 provides a perspective view of an outboard end of an exemplarysleeve of the present invention.

FIG. 7 provides a perspective view of an inboard end of the exemplarysleeve of FIG. 6.

FIG. 8 provides an end view, from the outboard side, of the exemplarysleeve of FIG. 6.

FIG. 9 is a cross-sectional view of the exemplary sleeve taken along thelongitudinal axis of the sleeve.

FIGS. 10, 11, and 12 are partial cross-sectional views, along line 10-10of FIG. 4, of an exemplary sleeve and flange. Different circumferentialpositions of the sleeve relative to the flange are depicted in eachfigure as more fully described herein.

FIG. 13 is a perspective view of an inboard side of an exemplary washerof the present invention.

FIGS. 14 and 15 provide perspective views of an exemplary flange and theinboard end of an exemplary sleeve of the present invention.

DETAILED DESCRIPTION

For purposes of describing the invention, reference now will be made indetail to embodiments of the invention, one or more examples of whichare illustrated in the drawings. Each example is provided by way ofexplanation of the invention, not limitation of the invention. In fact,it will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the scope or spirit of the invention. Forinstance, features illustrated or described as part of one embodiment,can be used with another embodiment to yield a still further embodiment.Thus, it is intended that the present invention covers suchmodifications and variations as come within the scope of the appendedclaims and their equivalents.

For this disclosure, the following terms are defined as follows:

“Axial direction,” or the letter “A” without a subscript in the figures,refers to a direction parallel to the axis of rotation of, for example,the hub or the wheel as it travels along a road surface. As used in thefigures herein, the vertical direction V is orthogonal to the axialdirection and the horizontal direction H is parallel to the axialdirection A.

“Radial direction” or the letter “R” in the figures refers to adirection that is orthogonal to the axial direction and extends in thesame direction as any radius that extends orthogonally from the axialdirection.

“Inboard” refers to a direction along axial direction A that is towardsthe vehicle and is designated with the letter I.

“Outboard” refers to a direction along axial direction A that is awayfrom the vehicle and is designated with the letter O.

“Surface of revolution” or the letters AR is the surface in Euclideanspace that is formed by rotating a curve or line around a straight line(referred to herein as the axis) in its plane.

“Wheel plane” or the letters “WP” is a plane passing down the center ofthe wheel (including the tire) and dividing the wheel into two equal,circular portions.

“Toe” or the letter “T” means the angle of the wheel plane WP withrespect to a longitudinal axis along the center of the vehicle.

“Camber” or the letter “C” means the angle of the wheel plane WP withrespect to the vertical axis VA of the vehicle. As used herein, when thewheel plane is parallel to the vertical direction and orthogonal to theaxial direction, both camber and toe are considered to be at zero—i.e.in a position of no camber or toe correction of the wheel alignment.

“Vehicle” includes motorized vehicles and non-motorized vehiclesincluding trailers.

“Factor” refers to numbers multiplied together to obtain another number.

“Greatest common factor” or GCF of two numbers means the integer that isthe greatest factor which can divide the two numbers.

FIGS. 3, 4, and 5 illustrate an exemplary assembly 100 of the presentinvention as may be used to make adjustments to camber, toe, and thrustby adjusting the alignment of the axis of rotation of a hub 102 relativeto a spindle 104 positioned at the end of an axle 106. Hub 102 isretained onto axle 106 by an axle nut 108 (also referred to as a spindlenut) that engages complementary threads 110 on threaded end 112 ofspindle 104. A clip 196 is received into teeth 198 (FIG. 5) of axle nut108. Clip 196 includes a tab 270 received into groove 136 to prevent nut109 from turning once tightened onto spindle 104. Hub 102 is rotatableabout spindle 104.

A plurality of threaded lugs 114 may be used with complementaryfasteners for securing a wheel or wheel rim onto assembly 100. Wheelassembly 100 may be used on a heavy commercial vehicle such as a traileror other vehicle types as well. Hub 102 and axle nut 108 are provided byway of example—other hub types and mechanisms of attachment to axle 106may also be used.

As shown in the cross-sectional view of FIG. 4 and in FIG. 5, spindle104 has an outer surface of revolution SR₀ about a spindle axis AR₀ thatis located at the center of spindle 104. For this exemplary embodiment,assembly 100 includes a cylindrically-shaped sleeve 116 that is machinedwith an internal diameter such that spindle 104 can be received withinthe interior 118 of sleeve 116 and onto outer surface SR₀.

As shown in FIGS. 4, and 6 through 9, sleeve 116 has an inner surface ofrevolution SR₁ about a first axis AR₁. When spindle 104 is matinglyreceived within the interior 118 of spindle sleeve 116 as shown in FIG.4, spindle axis AR₀ and first axis AR₁ are coincident with other or i.e.geometrically the same. As also shown, spindle sleeve 116 has an outersurface of revolution SR₂ about a second axis AR₂ that forms apredetermined angle α relative first axis AR₁. Different sleeves 116 canbe manufactured with different predetermined values for angle α. In oneexemplary embodiment, angle α has degree value that is within the rangeof 0.1°≤α≤0.7°. In still another exemplary embodiment, angle α has valueof 0.3°. Other values may be used as well.

The cross-section of FIG. 4 is selected for purposes of illustrating themaximum value of angle α. It should be appreciated that in across-sectional view that is orthogonal to the view shown in FIG. 5, itwould appear that the value of angle α is zero. Thus, as used herein,angle α refers to the angle value as measured within a plane containing(i.e. coplanar with) first axis AR₁ and second axis AR₂. Additionally,as used herein, angle α also refers to the absolute value of the anglebetween first axis AR₁ and second axis AR₂ on the inboard side of theintersection IX of these two axes as depicted in FIG. 4.

The present invention allows the circumferential position (i.e. thelocation along circumferential direction C) of angle α about first axisAR₁ to be selectively determined in order to make changes in toe,camber, and thrust for a wheel mounted on hub 102. Such adjustment isaccomplished by rotations of sleeve 116 to achieve the desiredcircumferential orientation of sleeve 116 relative to axle 106 as willbe further described.

For example, referring specifically to FIG. 8 (a view of sleeve 116 froman outboard end), by locating axes AR₁ and AR₂ both within a verticalplane VP (a plane parallel to vertical direction V), positive ornegative changes in camber can be accomplished. Positive camber can becreated by positioning second axis AR₂ and angle α above first axis AR₁within vertical plane VP as indicated by +C. Negative camber can becreated by positioning second axis AR₂ and angle α below first axis AR₁within vertical plane VP as indicated by −C.

Similarly, by locating axes AR₁ and AR₂ both within a horizontal planeHP (a plane parallel to horizontal direction H), positive or negativechanges in toe can be accomplished. Positive toe can be created bypositioning second axis AR₂ and angle α in front of first axis AR₁(front being relative to the forward direction of vehicle travel or FDTas shown in FIG. 2) within horizontal plane HP as indicated by +T.Negative toe can be created by positioning second axis AR₂ and angle αbehind first axis AR₁ relative to the forward direction of vehicletravel FDT within horizontal plane HP as indicated by −T.

Changes in both camber and toe can be effected by combinations whereaxes AR₁ and AR₂ (and angle α) are at locations between horizontal planeHP and vertical plane VP. Accordingly, positive or negative changes incamber, positive or negative changes in toe, as well as adjustments tothrust can be accomplished simultaneously depending upon thecircumferential orientation of sleeve 116 relative to spindle 104. Thevalue of predetermined angle α as well as its circumferential location(i.e. the location of sleeve outer surface axis AR₂ relative tohorizontal plane HP, vertical plane VP, and forward direction of travelFDT) will control the amount of camber, toe, and thrust adjustment thatoccurs using sleeve 116.

As now described, certain features are provided to fix thecircumferential position of sleeve 116 during use so that e.g.,rotational torque from rotation of a wheel on hub 102 does not changesleeve 116's circumferential orientation once set. At the same time,such features allow the circumferential position of sleeve 116 to bereadily adjusted.

FIGS. 10, 11, and 12 provide partial cross-sectional views, along line10-10 of FIG. 4, of sleeve 116 (shown in cross-section), spindle 104,and a flange 158 of axle 106. Different circumferential positions of thesleeve 116 relative to flange 158 are depicted in each figure as will befurther described. In this exemplary embodiment, sleeve 116 includes afirst plurality of apertures 122A, 124B, 126C, 128B, and 130A. Flange158 includes a second plurality of apertures 142A, 144B, 146C, 148B, and150A (shown in dashed circles to indicate their position behind sleeve116 in this end view).

The letters A, B, and C used with each aperture number denote aperturesthat are located at the same radial distance from first axis AR₁. Moreparticularly, as shown in FIG. 10, apertures 124B and 144B arepositioned at the same radial distance—denoted with R_(B)—from firstaxis AR₁. As shown in FIG. 12, apertures 130A and 150A are positioned atthe same radial distance—denoted with R_(A)—from first axis AR₁.

Referring to FIG. 11, central aperture 126C and central aperture 146Care positioned at the same radial distance—denoted with R_(C)—from firstaxis AR₁. For this embodiment, apertures 126C and 146C are alsocentrally located in that the positioning of all other apertures issymmetrical about a vertical plane VP passing through the middle ofcentral apertures 126C and 146C. In other embodiments of the invention,a different number of apertures may be used including both odd and evenamounts.

Used together, the first and second plurality of apertures provide aplurality of matching pairs of apertures that can be aligned along theaxial direction by rotation of sleeve 116. For this exemplaryembodiment, such matching pairs include:

-   -   122A and 142A;    -   124B and 144B;    -   126C and 146C;    -   128B and 148B; and    -   130A and 150A.

Each such matching pair can be aligned along the axial direction toprovide a discrete, predetermined amount of correction to the wheelalignment. A removable lock—in this exemplary embodiment a pin 160 (FIG.3)—extends between the apertures of the matching pairs to fix thecircumferential position of sleeve 116 relative to spindle 104 once thedesired circumferential position is selected.

By way of example, FIG. 11 depicts a central circumferential positionfor sleeve 116 relative to spindle 104 where the matching pair ofcentral apertures 126C, 146C are aligned along the axial direction. Pin160 (see FIG. 4) is inserted through each aperture 126C and 146C to fixthe position of sleeve 116 relative to spindle 104 and thereby preventsleeve 116 from freely rotating about spindle 104. For this exemplaryembodiment of assembly 100, the position in FIG. 11 aligns wheel planeWP with a predetermined amount of positive camber only and a zero amountof toe because angle α (always referenced herein with respect to itsvalue and location on the inboard side of intersection IX in FIG. 4) isabove the horizontal plane HP and positioned wholly within the verticalplane VP (see above discussion regarding FIG. 8). The amount of camberin this position depends upon the magnitude of angle α.

FIG. 10 depicts a circumferential position for sleeve 116 relative tospindle 104 where matching pair of apertures 124B, 144B are alignedalong the axial direction. Starting from a position as shown in FIG. 11,sleeve 116 is rotated counter clockwise (CCW) to obtain the positionshown in FIG. 10. Pin 160 is inserted through each aperture 124B and144B (FIG. 4) to fix the position of sleeve 116 relative to spindle 104and thereby prevent sleeve 116 from freely rotating about spindle 104.For this exemplary embodiment of assembly 100, the circumferentialposition in FIG. 10 orients wheel plane WP with a predetermined amountof positive camber and negative toe because angle α is above thehorizontal plane HP and behind the vertical plane VP (see abovediscussion regarding FIG. 8). The amount of camber and toe in thisposition depends upon the magnitude of angle α and the amount by whichsleeve 116 must be rotated from the circumferential position shown inFIG. 11 to the circumferential position shown in FIG. 10 so as to alignapertures 124B and 144B. In turn, the amount of such rotation iscontrolled by the number of apertures and the amount of spacing alongthe circumferential direction C between such apertures. Stateddifferently, the amount of such rotation depends on the distance alongcircumferential direction C between apertures 124B and 144B from thecentral apertures 126C and 146C, respectively. For example, angle α andthe circumferential spacing between apertures C could be such thatrotation from the position shown in FIG. 11 to the position shown inFIG. 10 provides a 0.05 degree change in toe.

Similarly, FIG. 12 depicts a circumferential position for sleeve 116relative to spindle 104 where matching pair of apertures 130A, 150A arealigned along the axial direction. Starting from a position as shown inFIG. 11, sleeve 116 is rotated clockwise (CW) to obtain the positionshown in FIG. 12. Pin 160 is inserted through each aperture 130A and150A (FIG. 4) to fix the position of sleeve 116 relative to spindle 104and thereby prevent sleeve 116 from freely rotating about spindle 104.For this exemplary embodiment of assembly 100, the circumferentialposition in FIG. 12 orients wheel plane WP with a predetermined amountof positive camber and positive toe because angle α is above thehorizontal plane HP and in front of the vertical plane VP (see abovediscussion regarding FIG. 8). The amount of camber and toe in thisposition depends upon the magnitude of angle α and the amount by whichsleeve 116 must be rotated from the circumferential position shown inFIG. 11 to the circumferential position shown in FIG. 12. In turn, theamount of such rotation is controlled by the number of apertures and theamount of spacing along the circumferential direction C between suchapertures. For example, angle α and the circumferential spacing betweenapertures C could be such that rotation from the position shown in FIG.11 to the position shown in FIG. 11 provides a 0.15 degree change intoe.

Returning to FIG. 4, the intersection IX of axis AR₁ and axis AR₂, canbe chosen so as to maintain alignment of any brake friction surfaces,such as brake pads against a disc, or a brake shoes against a brakedrum, such that the brake friction surfaces remain as close to the samealignment as was originally intended prior to the camber, toe and orthrust angle adjustment of the spindle sleeve 116. In some exemplaryembodiments of assembly 100, intersection point IX is chosen bypositioning axes AR₁ and AR₂ such that intersection IX is locatedbetween the brake friction surfaces thereby minimizing brake componentoffset.

The magnitude of predetermined angle α is used to control the amount ofwheel alignment that can be achieved through rotation of sleeve 116. Inturn, the magnitude of predetermined angle α is limited by the thicknessT (FIG. 9) of spindle sleeve 116. Thickness T must be of a magnitude toprevent deformation during handling of sleeve 116, installation of thesleeve 116 upon the spindle 104, or operation of the vehicle as theloads are transmitted from the vehicle through the spindle 104, spindlesleeve 116, wheel bearings 170, 180, hub 102 and to the road surface RS(FIG. 1).

Returning to FIGS. 4 and 5, a bearing spacer 188 allows excess axialforces to transfer through spacer 188 rather than bearings 170 and 180so as to “preset” the bearing load. Bearing spacer 188 is machined toexact dimensions and matched relative to the dimensions of hub 102 thatdefine the spacing between inboard bearing 170 and outboard bearing 180.It should be understood, that while this embodiment incorporates abearing spacer 188 for ease of installation and ensuring proper bearingpreload, other embodiments may omit the spacer 188. Bearings 170 arepositioned between outboard races 184 and 190 while bearings 180 arepositioned between races 186 and 192.

Referring now to FIGS. 6 through 9, the thickness T of sleeve 116 asmeasured from inner surface SR₁ to outer surface SR₂ varies dependingupon the azimuth location and longitudinal location along sleeve 116. Asalready described, these variations in thickness allow changes in wheelalignment based on rotation of sleeve 116 about spindle 104.

An inboard spindle sleeve bearing surface 204 is manufactured to a sizethat will receive a cone or inner race of the inboard bearing 180. Anoutboard spindle sleeve bearing surface 206 is manufactured to a sizethat will receive a cone or inner race of the outboard bearing 170.

A reduced diameter surface 208 between inboard bearing surface 204 andoutboard bearing surface 206 having a diameter less than the inboardbearing surface 204 eases assembly of inboard bearing 180 onto spindlesleeve 116. In this embodiment, reduced diameter surface 208 transitionsto inboard bearing surface 204 with a first angled chamfer 210. Reduceddiameter surface 208 transitions to outboard bearing surface 206 with asecond angled chamfer 212. Inboard bearing surface 204 and outboardbearing surface 206 have diameters in this exemplary embodiment that areidentical. However, other embodiments may have the outboard bearingsurface 206 smaller than the inboard bearing surface 204, such as foundin TN/TQ series bearings or TR series bearings.

As shown in FIGS. 7 and 9, sleeve 116 has a seal surface 214 that, inthis embodiment, has an appreciable larger diameter than inboard bearingsurface 204. Other embodiments within the scope of the invention mayhave a seal surface 214 with a diameter equal to that of inboard bearingsurface 204. In this embodiment, the inboard portion of sleeve innersurface SR₁ possesses a groove 216 in which a seal 218 (FIG. 4), such asan o-ring type seal, is placed to prevent leakage of lubricant from theinner part of the hub or from the ingress of contaminants.

FIG. 8 depicts an end view of sleeve 116 from outboard end 162. For thisorientation, sleeve 116 in this embodiment is thinner at the top than atthe bottom as a result of the relative positioning of the axis AR₂relative to axis AR₁. Inner surface SR₁ can be observed along the tophalf of sleeve 116 from this view since the inner surface axis AR₁ isangled down and away from the point of view of the figure. In thisembodiment, no appreciable toe angle is present. However, it can beappreciated that a variation in the circumferential position of angleα—or axis AR₂ relative to AR₁—would result in a change in the wheelalignment.

Referring now to FIGS. 3 and 13, assembly 100 includes a washer 132 thatis positioned between axle nut 108 and outboard end 162 of sleeve 116.Washer 132 has an inboard side 154 and an outboard side 156. The inboardside 154 defines a recess 166 into which the outboard end 162 of sleeve116 is removably received. A tab 138 extends radially inward from aradially inner surface 152 of washer 132 and is received into anaxially-oriented groove 168 (FIGS. 6 and 9) on the outboard end ofsleeve 116. As such, tab 138 and groove 168 provide means for fixing thecircumferential orientation of washer 132 so as to prevent rotation ofwasher 132 relative to sleeve 116.

Accordingly, assembly 100 can be used to adjust the alignment of a wheelplane WP on a vehicle 60 (FIGS. 1 and 2). In one exemplary method, axlenut 108 is loosened so that sleeve 116 can be shifted in the outboarddirection (O) away from flange 158. The amount of movement must beenough to allow for pin 160 to be disengaged and permit the rotation ofsleeve 116 relative to spindle 104. Depending upon the amount of e.g.,toe or camber correction desired and the direction (positive ornegative) of the desired toe correction, sleeve 116 is rotated clockwiseor counterclockwise as described above with regard to FIGS. 10, 11, and12 so to select the desired matching pair of apertures. Once selected,sleeve 116 is shifted along the inboard direction (I) and pin 160 isreengaged with flange 158 (i.e. pin 160 is positioned within thematching pair of apertures selected) so as to prevent rotation of sleeve116 relative so spindle 104. Axle nut 108 can then be tightened tosecure assembly 100. Other exemplary methods of adjusting thecircumferential position of sleeve 116 may be used as well.

As stated, the amount of rotation of sleeve 116 that is required toachieve a specific change in camber, toe, and thrust is controlled bye.g., the magnitude of angle α as well as the number and spacing of thefirst and second plurality of apertures on flange 158 and the inboardend 162 of sleeve 116. The radial distance between axis AR_(O) and thecenter of each aperture also affects the amount of change in alignmentthat occurs when rotating sleeve 116 between matching pairs ofapertures. As will now be further described, numerous arrangements ofthe matching pairs of apertures can be provided based on the range andmagnitude of adjustability needed for an exemplary wheel alignmentassembly of the present invention.

FIG. 14 depicts an exemplary flange 300 of an axle that is to be joinedwith the inboard end of a sleeve 400. For purposes of illustration,portions of the axle that support flange 300 as well as portions ofsleeve 400 have been removed. As previously described, sleeve 400 isrotated about the axle's spindle to the desired position for wheelalignment. At least one of the first plurality of axially-orientedapertures 404 on sleeve 400 and at least one of the second plurality ofaxially-oriented apertures 304 of flange 300 are aligned at the desiredposition as a matching pair of apertures. A locking mechanism such as apin is extended axially into the matching pair to prevent rotation ofsleeve 400 relative to the axle and flange 300 as previously described.

In an exemplary method of the present invention, let FP_(TOT) representthe total number of apertures chosen for the first plurality ofapertures 404 on sleeve 400. For exemplary sleeve 400 in FIG. 14,FP_(TOT)=8. Similarly, let SP _(TOT) represent the total number ofapertures chosen for the second plurality of apertures 304 on flange300. For exemplary flange 300 in FIG. 14, FP_(TOT)=12.

Notably, for this exemplary embodiment, apertures 304 and 404 are all atthe same radial distance R_(D) from axis AR_(O) (which is identical toAR₁—the axis of the inner surface of revolution of the sleeve 400). Assuch, the maximum number of matching pairs of apertures that can becreated at any single circumferential orientation of sleeve 400 relativeto AR_(O) is equal to the greatest common factor (GCF) of FP_(TOT)^(and SP) _(TOT). For the exemplary flange 300 and sleeve 400 of FIG.14, the GCF would be four.

More particularly, the maximum number of matching pairs of apertures 304and 404 that can be created at any single circumferential orientation ofsleeve 400 relative to AR_(O) and flange 300 is four. Thus, four pinscould be used to engage flange 300 and sleeve 400 in such position. Atthe same time, 24 unique positions can be created through rotation ofsleeve 400 relative to flange 300. Indicia 302 and 402 can be used tometer the correct amount of relative rotation.

To ensure that only one matching pair exists between the first andsecond plurality of apertures on the sleeve and flange, respectively,FP_(TOT) and SP _(TOT) must be selected such that their GCF is theinteger 1. Knowing that the values of FP_(TOT) and SP _(TOT) can bedetermined to create only a single matching pair of apertures at a timeduring the revolution of the sleeve is very useful in designingexemplary embodiments of a wheel alignment system of the presentinvention.

By way of example, referring to FIG. 15, a designer can choose the totalnumber of the second plurality of apertures SP_(TOT) of a flange 500based on e.g., the number of positions of toe and camber adjustmentdesired for the assembly 100. Assume again the designer chooses a totalnumber of 12 positions for SP_(TOT). Accordingly, 12 apertures arepositioned uniformly apart from each other along the circumferentialdirection C with each at a predetermined radial distance R_(O) relativeto AR_(O).

In order to provide only one matching pair of apertures at a time assleeve 600 is rotated relative to flange 500, the total number of thefirst plurality of apertures FP_(TOT) of sleeve 600 must be selected sothat the GCF of FP_(TOT) and SP_(TOT) is the integer 1. For the exampleof FIG. 15, such occurs when FP_(TOT) is equal to 7. Accordingly, whilethere are 84 (the product of 12 and 7) unique matching pairs ofapertures created by the rotation of sleeve 600 relative to flange 500,only one matching pair at any one time can be aligned (i.e. indexed)along the axial direction. Stated differently, only one pin or otherlocking mechanism can be extended between flange 500 and sleeve 600 atany one time as sleeve 600 is rotated about the circumferentialdirection relative to flange 500. Indicia 502 and 602 can be used tometer the correct amount of relative rotation.

As will be understood using the teachings disclosed herein, the positiveinteger values that can be used for FP_(TOT) and SP _(TOT) can be variedsubstantially to provide a wide range of adjustability of the sleeve andflange. For example, the number of apertures for FP_(TOT), SP_(TOT), orboth, can be varied to determine the number of indexed positions thatare available. If the GCF is the integer 1, then a single matching pairof aligned apertures at any one time can be ensured for rotations of thesleeve.

While the present subject matter has been described in detail withrespect to specific exemplary embodiments and methods thereof, it willbe appreciated that those skilled in the art, upon attaining anunderstanding of the foregoing may readily produce alterations to,variations of, and equivalents to such embodiments. Accordingly, thescope of the present disclosure is by way of example rather than by wayof limitation, and the subject disclosure does not preclude inclusion ofsuch modifications, variations and/or additions to the present subjectmatter as would be readily apparent to one of ordinary skill in the artusing the teachings disclosed herein.

What is claimed is:
 1. A method for indexing a wheel alignment systemfor a vehicle, the wheel alignment system including an axle definingaxial, radial, and circumferential directions, the axle comprising aflange and a spindle onto which a sleeve is rotatably received, the axlehaving an outer surface of revolution about an axis AR_(O), the methodcomprising the steps of: choosing a total number FP_(TOT) of a firstplurality of axially-oriented apertures for positioning on the sleeve;positioning the first plurality of apertures on the sleeve at locationsuniformly apart from each other along the circumferential direction witheach at a predetermined radial distance from axis AR_(O); selecting atotal number SP_(TOT) of a second plurality of axially-orientedapertures for positioning on the flange, wherein SP_(TOT) and FP_(TOT)do not share any common factors other than integer 1; and positioningthe second plurality of apertures on the flange at locations uniformlyapart from each other along the circumferential direction and at thepredetermined radial distance from axis AR_(O); wherein the first andsecond plurality of apertures provide a plurality of matching pairs ofapertures that can be aligned along the axial direction by rotation ofthe sleeve to provide changes in wheel alignment.
 2. The method forindexing a wheel alignment system for a vehicle as in claim 1, whereinrotation of the sleeve about the spindle aligns only one matching pairof apertures at a time.
 3. The method for indexing a wheel alignmentsystem for a vehicle as in claim 1, further comprising the step oflocking the circumferential position of the sleeve relative the spindle.4. The method for indexing a wheel alignment system for a vehicle as inclaim 1, wherein the step of locking comprises extending a pin betweenthe matching pair of apertures.
 5. The method for indexing a wheelalignment system for a vehicle as in claim 1, wherein the step ofchoosing a total number SP_(TOT) of a second plurality ofaxially-oriented apertures comprises determining an amount of change intoe and camber of the wheel alignment to be achieved by rotating thesleeve between matching pairs of apertures.
 6. The method for indexing awheel alignment system for a vehicle as in claim 1, wherein the sleevehas an inner surface of revolution about a first axis AR₁ and an outersurface of revolution about a second axis AR₂, wherein the first axisAR₁ and the second axis AR₂ are at a non-zero angle α from each other,and wherein the sleeve defines an interior into which the spindle isreleasably received.
 7. The method for indexing a wheel alignment systemfor a vehicle as in claim 6, wherein angle α is in the range of0.1°≤α≤0.7°.
 8. The method allowing selective adjustment of wheelalignment on a vehicle as in claim 7, wherein angle α is about 0.3°. 9.An assembly allowing selective adjustment of wheel alignment on avehicle, comprising: an axle defining axial, radial, and circumferentialdirections, the axle comprising a flange and a spindle having anoutboard end and an inboard end; a first plurality of aperturespositioned at an inboard end of the sleeve and extending along the axialdirection, the first plurality of apertures spaced apart along thecircumferential direction and positioned at varying radial distancesfrom a first axis, wherein the total number of the first plurality ofapertures is FP_(TOT); a second plurality of apertures positioned on theflange near an inboard end of the spindle and extending along an axialdirection, the second plurality of apertures spaced apart along thecircumferential direction and positioned at varying radial distancesfrom the first axis, wherein the total number of the first plurality ofapertures is SP_(TOT), and wherein SP_(TOT) and FP_(TOT) do not shareany common factors other than integer 1; wherein the first and secondplurality of apertures provide a plurality of matching pairs ofapertures that can be aligned along the axial direction by rotation ofthe sleeve to provide changes in wheel alignment; and a removable lockextending between the apertures of one of the matching pairs ofapertures so as to prevent the rotation of the sleeve relative to thespindle.
 10. The assembly allowing selective adjustment of wheelalignment on a vehicle as in claim 9, wherein the removable lockcomprises a pin extending along the axial direction between theapertures of one of the matching pairs of apertures so as to prevent therotation of the sleeve relative to the spindle.
 11. The assemblyallowing selective adjustment of wheel alignment on a vehicle as inclaim 9, further comprising: a washer positioned along the outboard endof the spindle adjacent to the sleeve; and means for fixing thecircumferential orientation of the washer so as to prevent rotation ofthe washer relative to the sleeve.
 12. The assembly allowing selectiveadjustment of wheel alignment on a vehicle as in claim 11, wherein meansfor fixing the circumferential orientation of the washer so as toprevent rotation of the washer relative to the spindle comprises: agroove positioned along the outboard end of the sleeve on the outersurface of revolution; and a tab extending radially inward from thewasher and received into the groove of the sleeve.
 13. The assemblyallowing selective adjustment of wheel alignment on a vehicle as inclaim 12, wherein the washer includes an inboard side defining recessinto which the outboard end of the sleeve is received, and wherein thetab extends into the recess.
 14. The assembly allowing selectiveadjustment of wheel alignment on a vehicle as in claim 13, wherein thewasher includes an inboard side defining a recess into which theoutboard end of the sleeve is received.
 15. The assembly allowingselective adjustment of wheel alignment on a vehicle as in claim 13,wherein the washer includes an outboard side, and wherein the assemblyfurther comprising an axle nut positioned adjacent to the washer incontact with the outboard side of the washer.
 16. The assembly allowingselective adjustment of wheel alignment on a vehicle as in claim 9,wherein angle α is in the range of 0.1°≤α≤0.7°.
 17. The assemblyallowing selective adjustment of wheel alignment on a vehicle as inclaim 16, wherein angle α is about 0.3°.
 18. The assembly allowingselective adjustment of wheel alignment on a vehicle as in claim 9,wherein the sleeve has a thickness that varies along an axial directionof the spindle.
 19. The assembly allowing selective adjustment of wheelalignment on a vehicle as in claim 9, wherein the first plurality ofapertures are positioned symmetrically about a central aperture of thefirst plurality of apertures; and the second plurality of apertures arepositioned symmetrically about a central aperture of the secondplurality of apertures.